Good Tillich and Buber Story

Since two of my greatest theological debts are to Martin Buber and Paul Tillich (there may be no Jewish thinker to whom I owe more than Buber, and there is certainly no Christian thinker to whom I owe more than Tillich), I read the essay "Buber and Tillich" in Jewish theologian David Novak's Talking With Christians with great interest. It is a very interesting and important essay, and I may write a serious engagement with it later. However, what interests me most at the moment is a story that Novak relays. So, for the moment, let me simply share it with you:

...the relationship between the older Buber and the younger Tillich [Buber, born in 1878, was eight years older than Tillich, born in 1886. They both died in 1965. - CB] is best illustrated by the following story that I heard from someone who was in attendance at a lecture Buber delivered at Union Theological Seminary in New York in 1952, during his first visit to America, a visit that made a profound impression on American intellectual circles. At the end of the lecture, Buber indicated that he would entertain questions from the audience. From the back of the crowded lecture hall, Paul Tillich arose and quite respectfully (as was his usual manner) addressed a rather complicated question to Buber. According to my reliable informant, Buber looked up from his text and said, "Ah, Paulus, it is you." The he walked down the aisle and stood directly in front of Tillich, who was considerably taller than he, raised his index finger up at Tillich's startled face and said, "Paulus, Paulus, you asked me the same question in Germany thirty years ago. Don't you remember what I answered you then?!"